Geologic formations can have many uses such as hydrocarbon production, geothermal production, and carbon dioxide sequestration. Logging tools are conveyed through boreholes penetrating the formations in order to perform measurements related to an intended use of the formation. Typically, the logging tools include sensors, transducers and/or transponders used in performing and processing the measurements. These devices generally require electrical power. However, the small space available in downhole logging tools due to the diameter of the borehole may limit the size of a power source such as a battery. Hence, it would be appreciated in the drilling industry if power sources for downhole applications could be improved.